Laparoscopically Implantable Nerve-Stimulating Electrode (LINSE): Application to the Cavernous Nerve in Acute and Chronic Canine Models

Using a new laparoscopic procedure, we investigated stimulation of the cavernous nerves to achieve erection in a canine model. The technique was developed during acute experiments in four dogs, following which, chronic studies (4- to 6-weeks survival after surgery) were undertaken in three dogs. A monopolar cuff electrode was inserted laparoscopically by a transperitoneal approach and placed around the cavernous nerve. The leads were brought out to the subcutaneous space, where they were attached to stimulation receivers that could be activated by an external radiofrequency transmitter. An intracavernous pressure elevation indicative of successful stimulation was obtained acutely in five of eight cavernous nerves in the four acute-study dogs and in four of six nerves in the three chronic-study dogs. The implanted equipment associated with four of six cavernous nerves failed mechanically in the chronic-study animals, such that only two receiver-electrode sites were intact at the time of sacrifice 4 to 6 weeks later. Transmitter-driven stimulation of one of these two sets produced an intracavernous pressure rise above 100 cm H2O. We present this technique as part of the continuing evolution of laparoscopy as both a research and a clinical tool. The present use of the laparoscopically implantable nerve-stimulating electrode is a new animal research tool and a potential first step in the human application of the technology.